Matthew Rhys protective of Keri Russell

The real-life couple play a married pair of undercover KGB spies in the hit drama series and though their off-screen relationship makes getting intimate on camera less awkward, the 41-year-old actor still feels uneasy at the crew seeing his partner nude.

Asked if their relationship makes sex scenes less awkward, Matthew said: "There's that immediate thing where, like, physically you're comfortable together, and so that's fine, and you're not all ... 'I'm sorry if I do this'. ... 'Oh God' ... 'Oh, can someone get her a robe, please?'

"I get a little protective. I'm like, 'Can someone get her a f***in' robe, please?! She's standing there naked, we've cut for five seconds, Jesus Christ.'

"And they're like, 'Dude, this is the fourth season.' "

Meanwhile, 40-year-old Keri - who has son Sam, two months, with Matthew and son River, nine, and daughter Willa, four, from her marriage to Shane Deary - joked she hadn't been asked to do many sex scenes before 'The American's because of her "13-year-old boy's" physique.

She quipped in a joint interview with The Hollywood Reporter: "I know you might find it surprising, but people don't cast me for my voluptuous body all the time. 'We're looking for a woman with a 13-year-old boy's body. Who can we get? Yes, you!' "

Matthew added: "Don't say that because what does that say about me?"

And the actress admitted she "sort of loves" the sex scenes on the show because they are more about power than love and romance.

She said: "I will say I sort of love the use of it on our show because, at least in my experience being a woman, you usually have to do the most sexy, the most in love, the most romantic version. In our show, I'm in a place of power: it's to get information from that person or to make that person feel a certain way. And that can be empowering."